Scientists Build A Working Tractor Beam

Alex Knapp
,
Forbes Staff
I write about the future of science, technology, and culture.

In the future of the Star Trek series, the crew of the U.S.S. Enterprise would occasionally need to tow another ship. When they did so, they didn't pull out the tow cables - they used a beam of light called a tractor beam to pull the other ship.

The main challenge to building a tractor beam is pretty intuitive. When a stream of light hits an object, it tends to move in the direction that the light is. However, some recent research has shown that with the right geometries, small microparticles can move in the opposite direction of the stream of photons.

Building on this previous research, the team constructed a beam of light and tested it on polystyrene particles with varying sizes - some were 400 nm, others were 1000 nm. The researchers weren't only able to pull them with their tractor beam, they were actually able to manipulate the beam to only pull certain particles. In other words, they could adjust the beam to only pull the 400 nm particles, then change it to only pull the 1000 nm particles.

That has an exciting application to medical testing. If this process can be refined to be used with biological particles, it could be possible to use it to sort items within a blood sample. That could make a huge difference in the ability to diagnoses disease and understand how it works.

"These methods are opening new opportunities for fundamental phonics as well as applications for life-sciences," said research team member Dr. Brzobohaty in a press release.

With this experimental success, it'll be fascinating to see some of the applications to come out of this. Just one thing, though - don't expect these tractor beams to be pulling spaceships anytime soon. Right now, those applications are pretty limited to microscopic particles. That doesn't make this any less of an achievement, however.

"The whole team have spent a number of years investigating various configurations of particles delivery by light," added team member Professor Zemanek in the release. "I am proud our results were recognized in this very competitive environment and I am looking forward to new experiments and applications. It is a very exciting time."